While it's far too early to suggest that this is a trend, it is interesting to note that in the latest Fox News Poll, Ron Paul claimed 2% of the vote, up from 1% about 3 weeks ago, and not even registering 6 weeks ago. In terms of pure rankings, that poll (taken June 5 & 6) puts Paul in a current 7th place out of a field of 13 that is including Fred Thompson, Newt Gingrich and Chuck Hagel, in addition to the 10 who have been participating in the debates.
What the poll trends do suggest, I think, based on their declining numbers (neither is even registering anymore) is that neither Sam Brownback nore Jim Gilmore seem to have much to offer anymore, and it might be better for them to just bow out soon, rather than to prolong the agony. Tancredo and Hunter register, but trail behind unannounced candidate Hagel (all with 1%). Tommy Thompson is still inexplicably showing up just below Ron Paul with 2%--I have no idea why, other than maybe some respondents hear Thompson and think Fred--or they just like the idea of someone named Tommy being President!